The OCHRE Ontology, RDF Statements, and the “CHOIR” OWL Specification OCHRE makes use of an innovative graph database that facilitates the integration of ontologically heterogeneous data derived from multiple sources (i.e., data that has been recorded using different conceptual schemes and terminologies for describing the entities and relationships in a given domain of knowledge). The logical structure of the OCHRE database is specified in 23 XML document types suitable for an XQuery-based system. However, a more generalized expression of the OCHRE graph database structure using RDF triples, and thus suitable for other kinds of graph database software, has been provided by means of a Web Ontology Language (OWL) specification called CHOIR, a “Comprehensive Hermeneutic Ontology for Integrative Research.”

OCHRE is based on an abstract “upper” or top-level ontology within which domain-specific and project-specific ontologies can be subsumed as an aid to integration of ontologically heterogeneous data. The OWL CHOIR expression of this top-level ontology is used by the OCHRE software to specify classes, subclasses, and relations that constrain the structure and meaning of RDF triples exported from the OCHRE database or dynamically exposed on the Web for other software to consume. RDF triples are used in the Semantic Web to represent atomized subject-predicate-object statements of knowledge. RDF triples that conform to the OWL CHOIR ontology specification correspond to item-variable-value triples in the OCHRE database and preserve the high degree of atomization within that database. This allows the entities and relationships represented in the OCHRE database to be published on the Web in a way that preserves all their nuances and distinctions while conforming to the Semantic Web standards.

The OWL specification of CHOIR is currently under development and will be released soon with accompanying annotations and examples of RDF triples that conform to it. In the meantime, the philosophical principles underlying its design are explained below by way of comparison to other top-level ontologies designed to facilitate data integration. Development of the OWL specification of CHOIR is supported in part by the Neubauer Collegium for Culture and Society of the University of Chicago, as one component of a collaborative project on ontology-based data integration (“An Organon for the Information Age”) led by David Schloen (Professor of Near Eastern Archaeology), Malte Willer (Associate Professor of Philosophy), and Samuel Volchenboum (Associate Professor of Pediatrics and Associate Chief Research Informatics Officer).